“They are not where they need to be and won’t be until all of their troops ... are gone,” Hagel told the Post.

Even as the troops withdraw or prepare to do so, a NATO officer unnamed by the Post said actions lately "fundamentally changed" the region’s dynamics and said nothing would "erase or reverse what happened in recent months."

Another team, with four international members, already had been reported missing May 26, OSCE said.

Meanwhile, fighting continued in the country between government soldiers and rebels.

The downing of a Ukrainian military helicopter that killed a general and 13 soldiers this week and the disappearance of the OSCE monitoring missions have escalated tensions. President Barack Obama blamed “outside” forces for supplying the rebels with weapons.